I think you are a bit confusing "your Paypal business id/email" (ie. one used to receive payments from your customers); That one can be your business ID (given by Paypal) or your email associated with Paypal (u can have multiple). That email can be set in two levels as described in the article above, can be set on your account level (under MY ACCOUNT > Default Paypal Business ID/Email), and can be set as well at the funnel level (when creating/editing a funnel on our app). We've done that so we can allow you to use a different Paypal recipient account per funnel (if needed).
And the VIP EMAIL, ie. the one used to signup to the app, that email is not shown to your customers. It's only used by our backend system.
In either case, please follow the instructions as provided in the article above, and you'll be ready to go
Let me know if you have any other questions/concerns.
Hope that helps,